Dispersing Prisms are used to seperate a beam of white light into its component colors.Generally,the light is first collimated and then dispersed by the prism. A spectrum is then formed at the focal plane of a lens or curved mirror.In laser work, dispersing prisms are used to separate two wavelengths following the same beam path . Typically, the dispersed beams are permitted to trave lfar enough so the beams separate spatially. A prism exhibits magnification in the plane of dispersion if the entrance and exit angles for a beam differ. This is useful in anamorphic (one-directional) beam expansion or compression,and may be used to correct or create
asymmetric beam profiles.